With the advancement in scientific technologies and the modularization and miniaturization of camera lens, it is now possible to produce digital cameras having a very small volume, and most of currently available mobile phones are provided with the function of a digital camera. In a miniature lens, there are many different auto-focusing driving mechanisms.
FIG. 1 is an exploded perspective view of a conventional lens focusing structure. As shown, the lens focusing structure includes a front cover 10, a rear cover 11, an outer frame 13 being provided at four inner wall surfaces with a magnet 14 each, an lens holder 12 internally provided with screw threads 15 for a lens 16 to screw thereinto, a winding 17 wound around an outer side of the lens holder 12, and two plate springs 18 separately connected to a front and a rear end of the lens holder 12. The lens holder 12 is supported by the two plate springs 18 to axially movably locate in the outer frame 13 and be surrounded by the four magnets 14. When the winding 17 is supplied with an amount of current to thereby produce a magnetic field polarity, the lens holder 12 and the four magnets 14 mutually repulse or attract, bringing the lens holder 12 and the lens 16 to automatically focus.
In the conventional lens focusing mechanism, there is a front open inlet to facilitate convenient screwing of the lens 16 into the lens holder 12. For a camera device provided with the conventional lens focusing mechanism to provide an image shooting function, such as a mobile phone or a digital camera, an outer cover or case of the camera device is provided with a light-transmittable flat lens, such as a glass plate, so as to protect the lens. However, the lens is subject to dust or damage by external force in the process of assembling to form a half-finished product. On the other hand, when a glass plate is directly mounted to the open inlet of the lens focusing mechanism, the lens can be protected against damage and dust in the whole process of assembling, and the camera device using the lens focusing mechanism with a lens protective glass can omit the flat lens therefrom to largely reduce the manufacturing cost and the overall thickness thereof.
It is therefore tried by the inventor to develop an improved lens protection structure, so that a lens protective glass can be fixedly held to a lens inlet of the miniature lens focusing mechanism by a locating structure.